RISK-FACTORS AND CLINICAL IMPACT OF CENTRAL LINE INFECTIONS IN THE SURGICAL INTENSIVE-CARE UNIT

Objective: To determine the risk factors and clinical impact of centra l line infections in critically ill surgical patients. Design: Retrosp ective study. Setting: The surgical intensive care unit of a large ter tiary care university hospital. Patients: A total of 232 consecutive c entral line catheters sent for culture from patients in a surgical int ensive care unit during 1996 and 1997. Catheters were sent for microbi ologic analysis when the patient was clinically infected and the centr al line was a possible source. Interventions: None. Main Outcome Measu res: Risk factors associated and clinical impact of a positive cathete r culture. Results: Of 232 consecutive catheters from 93 patients sent for microbiologic analysis, 114 catheters (49%) had no growth, 40 (17 %) were colonized (<15 colonies), and 78 (34%) were considered infecte d (greater than or equal to 15 colonies). Univariate analysis showed t hat site (internal jugular vs subclavian, P<.001), catheter use (monit oring > dialysis > fluid > nutrition, P = .006), placement in the oper ating room vs the intensive care unit (P = .02), and placement of a ne w catheter (> guide wire, > new site, P = .003) were all significant f actors. Surprisingly, neither the number of lumens nor the duration of the catheter in situ were predictors when a catheter was suspected an d not proved infected compared with a suspected and proved catheter in fection. In the multiple regression model, the placement of the cathet er in the internal jugular position was the single most important pred ictor of a catheter infection (P<.001; odds ratio, 1.83; 95% confidenc e interval [CI], 1.41-2.37). The presence or absence of a specific cli nical sign of infection was not predictive of a proved catheter infect ion. Eighty-six percent of patients had gram-positive bacteria identif ied on the culture, while the remaining patients had gramnegative bact eria or Candida identified. Of the catheter infections, 68% were monom icrobial, whereas 32% were polymicrobial. Of the catheters sent for mi crobiologic analysis, 209 (90%) had concurrent peripheral blood cultur es for analysis. Nineteen (32%) with no growth from the catheter, and 14 (23%) of colonized catheters had concurrent bacteremia; all had ano ther identifiable cause of infection. Twenty-seven (45%) of infected c atheters had a concurrent bacteremia, and 9 of 27 had a second site po sitive for the same organism. Death related to the infection occurred in 15 patients, 2 in the first 72 hours and 13 in the following 14 day s. Conclusions: Central line infections remain an important cause of m orbidity and mortality. Comprehensive review of hospital practices may show a directed focus for performance improvement practices. At our i nstitution, internal jugular catheters have the highest rate of infect ion. This may suggest breaks in technique during catheter insertion or during catheter maintenance and care.